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Date: Wed, 7 Mar 2018 10:04:20 +0000
From: Will Deacon <will.deacon@arm.com>
To: Shanker Donthineni <shankerd@codeaurora.org>
Cc: Philip Elcan <pelcan@codeaurora.org>,
        Marc Zyngier <marc.zyngier@arm.com>,
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Subject: Re: [PATCH v6] arm64: Add support for new control bits CTR_EL0.DIC
 and CTR_EL0.IDC
Message-ID: <20180307100419.GA9111@arm.com>
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On Tue, Mar 06, 2018 at 01:33:00PM -0600, Shanker Donthineni wrote:
> > I also confirmed with Thomas Speier, we can skip __flush_icache_all() if DIC=1.

Thanks,

> Planning to patch __flush_icache_all() itself instead of changing the callers. This
> way we can avoid "ic ialluis" completely. Is this okay for you? 
> 
> static inline void __flush_icache_all(void)
> {
>        /* Instruction cache invalidation is not required for I/D coherence? */
>       if (!cpus_have_const_cap(ARM64_HAS_CACHE_DIC)) {
>                asm("ic ialluis");
>                dsb(ish);
>        }
> }

Yup, that's what I meant, cheers.

Will